Leveling device for cable-tool drills



iiiiiii n K. E. REISCHL LEVELING DEVICE FOR CABLE-TOOL DRILLS Filed Jan. l, 1945 June 17, 1947.

Patented June 1r, 1947 LEVELING DEVICE FOR CABLE-TOOL DRILLS Karl E. Reisehl, South Milwaukee, Wis., assignor to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application January 1, 1945, Serial No. 570,976

4 Claims.

My invention relates to new and useful `improvements in leveling devices for cable-tool drills.

The cable-tool drill is a highly specialized, but well-known, form of drill for drilling vertical holes in earth or rock. The drilling too is successively hoisted by a rope and th'en dropped against the bottom of the hole which is being drilled.

In the past it has been customary to block up the main frame of the machine with timbers before starting drilling. Mechanical jacks have sometimes been used, in place of such cribbing.

The objects of such jacking or cribbing have been: (l) to level the machine preliminary to drilling, this being especially necessary in view of the vertical nature of the drilling operation; (2) to broaden the support base beyond the limits of the traction mechanism, as otherwise the lifting and dropping of the drilling tools at a point beyond the traction base would introduce great instability; (3) to relevel during drilling; and (4) to protect the traction mechanism, and th'e connections between it and the main frame, from jarring strains.

The substitution of hydraulic jacks for mechanical jacks, would serve to speed-up the leveling operation, but would introduce no further advantages along the above lines; in fact, would introduce some further complications, as follows: The control-valves of an hydraulic jack system would not stand the strains imposed on the system by the drilling operation, and any attempt a1; introducing lateral stability would impose undue bending strains on the Avjacks themselves. Furthermore it would be necessary to protect the jacks themselves from external damage.

Neither cribbing nor jacks (not even hydraulic jacks) were adapted to releveling plus centering, and furthermore provided no lateral stability. Lateral stability is essential, to keep the line which suspends the drilling tools centered over the hole.

Accordingly the invention disclosed and claimed in copending application of Herbert W. Thornburg, for leveling device for cable-tool drills, Serial No. 553,437, led September 9, 1944, was devised by said Thornburg for the following objects: (1) to provide an hydraulic leveling system; (2) to provide a leveling system which will alford lateral stability; (3) to prevent the lateral stabilizing means from imposing bending strains on my hydraulicapparatus; (4) to protect my hydraulic -apparatus from external damage; and (5) to protect my control valvesfrom drilling shocks.

He attained these advantages by employing', instead of hydraulic jacks, telescoping spuds, rigidly attached to the main frame of my drill, and operated by hydraulic mechanism; by locating these hydraulic mechanisms inside the spuds, which latter are wholly enclosed so as to protect these mechanisms; by so connecting these operating mechanisms to the spuds, that the spuds take all the bending strains,`and the mechanisms are under merely pure compression; and finally by adding means to close the pressure conduit between each spud and its control-valve, during drilling.

In this connection, I contributed to his design one very important detail, namely a novel and useful improvement in telescoping spuds, which will now be described.

To attain the lateral stability so essential to the Thornburg invention, and to protect th'e hydraulic apparatus thereof from external damage, the outer (i. e., upper) section of the spud has to be rectangular in cross-section, in order that it may have adequate contact with the structure of the main frame of the machine. Preferably its rectangular cross-section should be a square, for purposes of symmetry withthe inner (i. e., lower) section.

From the mass production point of view, the guides to be built intothe outer section, to guide the inner section, should be readily assemblable.

For maximum sliding contact, and resistance to bending in all directions, the inner section should be cylindrical.

To protect the hydraulic apparatus within the spud from external damage, it is essential that both the outer section and the inner section of the spud be continuous, without openings.

Accordingly it is the principal object of my invention to provide a telescoping spud to the above specications.

A more specic object is to devise an outer section in which the guides for the inner section are readily assemblable.

In addition to my principal objects, above stated, I have worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which one embodiment is exemplied in the accompanying drawings, which are hereinafter particularly described and explained.

.Fhroughoutl the descriptionthe same: reference Y number is applied to the same member or to similar members.

Figure 1 is a side elevation of a cable-tool drill containing my invention.

inserted in the upper end of the hole being drilled,VIV

I3 is any convenient form of ground support for` the drill preferably but not necessarily V`of the endless tread variety. Y Y

A drilling-tool I4 is suspended in the hole by a rope I5, which passes over a crown-sheave (not shown) at the top of mast It, thence around spudding-sheave Il, on spudding-beam I8, thence around heel-sheave I9 at the rear pivot of beam i8, and thence to a winch drum 26. rlhe beam I8 is reciprocated by motor 23, acting through intermediate unnumbered gearing and crank 22 and pitman 2l. Various methods, well-known in the art, can be used to pay-out and take-in rope Tool IQ may be steadied by tool-guide 2t.

The description thus far is conventional and, as to its details, constitutes no part of my invention.

The Thornburg application, previously referred to, has added thereto front Spud 25 and two rear spuds 26, to give a three-point support to the machine during drilling.

Let us now turn to Figures 2 and 3, consider the details of each spud and its associated hy draulic operating mechanism.

First there is the telescoping spud, consisting of an outer casing 28, built rigid with channels 227 of' the frame ll, and a cylindrical inner casing 29. The outer casing 28 has a cap 3G, secured thereto in any convenient manner, as by bolts 3I. The inner casing 2S slides on guide-rings 32, secured to the outer casing in a manner to be hereinafter described.

Pivoted to the cap 3S, as at 33, is a cylinder 3e, containing a piston 35, and piston rod 35. The piston rod is pivotally attached to the inner spud casing 29, as at 3l.

The bottom end of the inner Spud casing is universally attached to a ground-engaging shoe 38, as at 39. If desired, the shoe V38 may have suction-relieving holes 4i).

The rigid attachment of the outer casing 28 to the main frame of the machine enables the spud to hold the machine against lateral movement.

'I'he placing of the cylinder-piston assembly inside the spud, causes the Spud to take all bending stresses, and places the cylinder-piston assembly under pure compression whenever the spud is under load. Also this construction protects the cylinder-piston assembly from dirt and other damage.

The Youter casing 28 is seen to be an elongated box of square cross-section, open at the ends. It is built preferably of structural steel, either two channels (or plates bent to form channels), or two angles (or plates bent to form angles), or four plates, welded together at the edges. In actual practice I prefer and use two plates each bent to form a channel, but this is not essential.

Each of my rings 32 is preferably either cast (internally machined or not), or made of baiJ f outer casing 28. Accordingly, to receive each of four equally spaced portions o f the circumference of my ring, I cut a rectangular hole 3| in my outer casing. If the diameter of ring 32 is merelyV equal tothe width of the outer casing, hole 4I need merely be large enough to Weld through.

Although a square cross-section for the outer casing is preferable, some other polygonal shape couldbe employed.

Assembly is accomplished as follows. The two or more structural pieces which constitute my outer'casing 28, are loosely put together, with my rings 32 projecting into or abutting holes 4 I. The structural pieces are thensecured tightly together in any convenient manner, and arewelded together along their abutting edges. The rings 32 are welded to some or all of the three or four edges of each hole l I. Y

The use of Va ring of larger outside diameter Vthan the inside width of the casing, all other things being equal, permits the ring to be built thicker and stronger, without any appreciable offsetting weakening of the body proper of the outer casing. f Itis to be noted that all welding is done vexternally, and that there is a Very small number of parts and of welded joints. These features are what render my invention so easy and inexpensiveto fabricate on a mass-production basis.

It is to be noted that the absence of gussets to secure the ring within the body proper of the casing, permits the extrusion of whatever mud may work its way inside the outer casing.

The outer casing, constructed as above, can

l. In an outer casing of aVtelescopingstrut',`

which strut comprises an outer casing, and an inner casing slidable within said Outer casing, vand means to force the two casings apart toincrease the effective length of the strut, the combination of: a hollow body of polygonal cross-section; andv at least one hollow cylindrical ring within thel body, with its axis lengthwiseY of the body; the body having, in the center of at least one sideja hole registering with the ring; the ring being welded to the body through said hole. 2. In an outer casing of a, telescoping strut, which strut comprises an outerV casing, and Yan inner casing slidable within said outer casing, and means'to force the Ytwo casings apart to increase 'the eiective length of the strut, the combination of: a hollow body of rectangular cross-section; and at least one hollow cylindrical ring within the body, the outer 'diameter of the ring being greater than the inner width of the bodyi the body having, in the center Yof each side a hole into which the ring projects, the edges of each Asuch hole being welded tothe ring. K Y

3. A casing according to claim 2, further characterized by the fact that the ring is of bar stock, with its ends Welded together. L

then be welded, or otherwise secured, to channels 4. A casing according to claim 2, furthel` characterzed by the fact that the body consists of The following references are of record in the file of this patent:

UNITED STATES PATENTS two plates, each in the form of a channel, and Number Name Date with their abutting edges Welded together. 2,252,741 Thornburg Aug. 19, 1941 KARL E REISCHL 5 2,204,365 Klemm June 11, 1940 2,365,169 Billings Dec. 17, 1944 REFERENCES CITED 1,920,131 B10111112 et 3.1. Aug. 1, 1933 

